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BIARRITZ, France — Boris Johnson made plenty of noise in Biarritz, but at critical moments, his bark proved worse than his bite.

The U.K. prime minister headed into one of his key meetings of his first major outing on the world stage — a 20-minute head-to-head with Donald Tusk during the G7 summit — on Sunday against a backdrop of newspaper reports claiming he would tell the European Council president the EU would lose out on up to £30 billion worth of U.K. financial obligations in the event of a no-deal Brexit.

But when it came to it, the issue didn’t even come up during their talk on the sidelines of the summit in the coastal French town, according to EU officials.

Indeed, for a prime minister who let it be known during his leadership campaign that he would retain the U.K.’s full £39 billion divorce bill, Downing Street’s acceptance that some money must be paid even in the event of no deal represents a climbdown of sorts.

The Sunday Times reported that U.K. government lawyers put the financial obligation in the event of no deal at between £7 billion and £10 billion, but following the Tusk meeting, Downing Street declined to put a figure on it.

There was also a sense of anti-climax about Johnson’s challenge to Donald Trump on trade.

The £39 billion was a figure “attached to the Withdrawal Agreement,” agreed by Theresa May, a U.K. government official said. “If we leave without a deal, then obviously the Withdrawal Agreement no longer stands.”

“If we are to leave without a deal, there will be substantial sums that we can spend domestically,” the official added, but didn’t say how much. Johnson “didn’t discuss figures,” the official said.

There was also a sense of anti-climax about Johnson’s challenge to Donald Trump on trade. The prime minister had positioned himself before the summit as a defender of the principles of free trade and open economies. But in comments to the press ahead of his one-hour meeting with the U.S. president, amid bellicose rhetoric from Trump on China, Johnson mustered only what he admitted was a “faint, sheep-like note of our view on the trade war.”

“We're in favor of trade peace on the whole, and dialing it down if we can,” he said. Trump barely seemed to notice.

Finding a way through

Johnson began his second summit day with a 7 a.m. swim in the Atlantic, a dip which he later used as part of an analogy for his Brexit strategy. Monitored by a French security team on paddleboards and boats and accompanied by the U.K.'s ambassador to France Ed Llewellyn, he said he had swum all the way round a rocky outcrop just off the beach.

"Let me give you a metaphor. I swam round that rock this morning. From here you cannot tell there is a gigantic hole in that rock. There is a way through," Johnson said during a TV interview later in the day. "My point to the EU is that there is a way through, but you can't find the way through if you just sit on the beach."

Actual detail on the way forward was in short supply, however.

Both sides said the Tusk-Johnson meeting took place in a positive atmosphere (Saturday's trading of "Mr. No Deal" barbs did not get a mention either). But there were few signs of progress. The EU is waiting for the U.K. to put forward what Tusk calls "credible alternatives" to the Northern Ireland backstop plan — a pillar of the Withdrawal Agreement — before they countenance a formal negotiation.

Reflecting the circular dispute in which the two sides find themselves, the U.K. official countered: “We’ve always been ready to talk … if you’re talking about a formal negotiation, the EU have to be willing to reopen the Withdrawal Agreement because the Withdrawal Agreement simply cannot pass through parliament."

The question of parliament, and what it will try to do to prevent Johnson from delivering on his pledge to take the U.K. out of the EU — deal or no deal — on October 31, continued to dog the prime minister during the summit.

Johnson himself told the BBC in Biarritz that the probability of a deal was now "touch and go."

"I am writing on behalf of all former ministers in the last administration to ask you to withdraw these allegations which question our integrity, acknowledge that no former minister could have leaked this document, and apologize for the misleading briefing from No. 10," Hammond wrote.

He and other anti-no deal Conservative MPs have indicated a willingness to back Johnson if he makes a genuine push for a deal with the EU. But their patience will run out quickly if there are no substantive talks soon, and a parliamentary move to block Johnson heading for no deal could happen as soon as MPs return to Westminster in early September.

Johnson himself told the BBC in Biarritz that the probability of a deal was now "touch and go" — a significant downgrade on his previous prediction that no deal was a "million to one" scenario.

So far, his Biarritz outing has given little cause to believe the trend will reverse any time soon.